In the past, the inventors of the present application have proposed a semiconductor light emitting element disclosed in Patent Literature 1. The semiconductor light emitting element disclosed in Patent Literature 1 includes an active layer, a pair of cladding layers between which the active layer is interposed, and a phase modulation layer optically coupled to the active layer, and the phase modulation layer includes a base layer and a plurality of different refractive index regions having different refractive indices from the basic layer. In a case where a square lattice is set in the phase modulation layer, the different refractive index region (main hole) is disposed so as to exactly coincide with a lattice point of a hole lattice. An auxiliary different refractive index region (sub hole) is provided around the different refractive index region, and light having a predetermined beam pattern can be emitted.